transient analysis
 

I have done static analysis in cfx.I have datas avalable were velocity (22 m/sec) and pressure(3.58 bar) at inlet,and pressure(3.69 bar) at outlet.I have given boundary conditionas as velocity at inlet and presurre at outlet.now at inlet pressure was varing sinusodially so i have made transient analysis.so i have made inlet at pressure and velocity at outlet.Now my question is whether this is right or wrong.because pressure at inlet and velo at outlet is physible for compressible flow.In my case there is no comp flow.so this is right or wrong?

as an another option i have tried that i have given veloc at inlet and pressure at outlet.And sinusodially vering pressure as an initialization.so is it right or wrong?In former case it has been solved and in later the solution is going on.